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What is Being Done to
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Ensure Safety on the Road
Modern Developments that Make for the Safety of the Vehicle are Discussed and Some of the Major Problems of the Highway Engineer Reviewed
I N any discussion on the subject of road safety there are three primary considerations that must be borne in mind. First, there is the question of the vehicle and its components, and bound up with this is the wide variety of problems concerning road planning, construction, lighting, etc.; to complete the trio, there is the important factor of the human element. Since the calculations of the engineers, responsible for both the vehicles and the roads, make— or should make—due allowances for the last-named we do not propose to deal with this aspect of the problem in this article.
The objects of recent developments in vehicle construction have been threefold, and the attainment of improved performance, with greater economy and increased safety, have rewarded the c48
efforts of designers. Improvements in steering, brakes, controls, tyres and lighting are largely responsible for the gain in safety, whilst the elimination of fire risks has also resulted from the development of the oil engine.
Light and accurate steering is an essential to road safety, and it may be confidently asserted that to-day even the heaviest vehicles satisfy this specific need. This fact is clearly supported by our experience in road testing a wide variety of machines, and it is rare indeed to find any cause for complaint in this respect.
Lightnws of the controls is another matter that has received attention, and from the safety viewpoint it -is im
portant in reducing fatigue. Drivercomfort has come under special notice and many commercial-vehicle cabs now give a high degree of comfort approaching that afforded in the modern private car. Adjustable squabs and driving seats are to be found in certain instances and, where the vehicles have to be handled by more than one driver, these features enable the • maximum comfort to be obtained.
Large-capacity batteries and efficient lams, with a dipping device for the headlamps, are in general use and, on long-distance services in particular, their employment makes for increased safety. In recent years, windscreen wipers have been improved and now give thoroughly reliable service, whilst the provision of fully adjustable windscreens and the use of one of the many available fog lamps have done Much to combat the dangers of fog.
Continued research by tyre manufacturers has resulted in transport operators obtaining increased niileages and greater reliability from their tyre equipment. Several processes for increasing the life of the tyre, when the tread has become worn, have come to the fore.
Amongst these may be mentioned the Pneugrippa process of Tecalemit, Ltd., which, it is claimed, not only lengthens the life of a tyre, but provides a constant safety factor -throughout its useful
lire. Tyres°les, Ltd., has developed an interesting retreading process, and equipment for recutting treads is made by the H. F. and Wilent concerns.
We have proved, during our road tests of a wide variety of commercial vehicles, that there is, to-day, a high standard of braking efficiency on all British chassis. Great strides have been made by the makers of shoe facings and much research work has been carried out in this connection. Road safety naturally requires that vehicle brakes should be thoroughly reliable and efficient in all circumstances and, broadly speaking, there are four distinct types of brake that fulfil this requirement.
The first is the straightforward servooperated system, and this is a popular type, for it calls for a light pedal pressure under all conditions. The Clayton Dewandre concern has' developed this system to a high degree, and another well-known servo system is that made by Feeny and Johnson, Ltd.
The second type is represented by the widely used Lockheed hydraulic system which is favoured for use on vehicles of all classes. A comparatively recent development is the combination of the hydraulic system with servo action.
Air-operated brakes are particularly suitable for trolleybuses, and the Westinghouse and Peters systems are extensively used. For the lighter classes of vehicle, mechanically operated selfenergizing brakes are popular and, perhaps, the best example of this system is the Bendix arrangement.
Before leaving the subject of brakes, mention should be made of the need for easy adjustment and, in this connection, the R.P. automatic adjuster, product of the Clayton-Dewandre concern, is noteworthy.
From the foregoing, it will be seen that vehicle designers have kept the safety problem in the forefront in their efforts to improve the breed and it remains but to outline the steps that arc being taken by road engineers.
Road planning and construction have not, in our view, kept pace with vehicle design. Whilst some attempts are now being made to build roads suitable for the traffic that uses them, instead of adapting the traffic to the roads, lack of vision on the part of the authorities concerned has tended to increase rather than diminish road dangers. Most of the 'efforts that have been made to promote safety on the roads have been of a restrictive nature and 'the problem of congestion—the greatest factor making for accidents—has received but tardy recognition.
The improvement of main traffic routes and the replanning, on a large scale, of many towns and villages, are essential if maximum road safety is to be assured; such schemes must be considered from the primary viewpoint of reducing congestion. Statistics prove that the largest number of accidents occurs during rush periods, partiallady when these coincide with the hours of darkness. At these times traffic speed is at its lowest and congestion is at its maximum, • thus the dangers of heavy traffic conditions are clearly demonstrated.
A bigger effort must, we think, be made to control pedestrians. Although the extensive provision of crossings has, in some quarters, been hailed as a brilliant move in safety promotion, in . practice it has been found impossible to persuade pedestrians to make full, proper and intelligent use of them, and their value is thus largely negatived.
Roundabouts, traffic lights, pedestrian crossings, etc., have played a useful part in controlling traffic, but there is still a sad lack of uniformity in road
surfaces, widths and lighting. Nonskid surfaces and modern lighting are essentials for road safety, whilst the two-way road with paths for cyclists and pedestrians should be the standard for all our main highways.
The Government must clearly accept responsibility for the inadequacy of our present road system, and for its inability to make senSible use of the brains and material at its disposal, so as to bring the national highways systern up to a standard suitable for immediate and potential needs. Both vehicle manufacturers and road engineers are mindful of the situation as it stands today and they have achieved much success in the face of ill-founded opposition. If the Government tackles the problem in the way that it should, many of the road difficulties of the pass can be eradicated.